JavaScript版本的《二叉搜索树中的搜索》

problems/0700.二叉搜索树中的搜索.md

@@ -290,7 +290,64 @@ func searchBST(root *TreeNode, val int) *TreeNode {
 }
 ```
 
+JavaScript版本
 
+> 递归
+
+```javascript
+/**
+ * Definition for a binary tree node.
+ * function TreeNode(val, left, right) {
+ *     this.val = (val===undefined ? 0 : val)
+ *     this.left = (left===undefined ? null : left)
+ *     this.right = (right===undefined ? null : right)
+ * }
+ */
+/**
+ * @param {TreeNode} root
+ * @param {number} val
+ * @return {TreeNode}
+ */
+var searchBST = function (root, val) {
+    if (!root || root.val === val) {
+        return root;
+    }
+    if (root.val > val)
+        return searchBST(root.left, val);
+    if (root.val < val)
+        return searchBST(root.right, val);
+    return null;
+};
+``` 
+
+> 迭代
+
+```javascript
+/**
+ * Definition for a binary tree node.
+ * function TreeNode(val, left, right) {
+ *     this.val = (val===undefined ? 0 : val)
+ *     this.left = (left===undefined ? null : left)
+ *     this.right = (right===undefined ? null : right)
+ * }
+ */
+/**
+ * @param {TreeNode} root
+ * @param {number} val
+ * @return {TreeNode}
+ */
+var searchBST = function (root, val) {
+    while (root !== null) {
+        if (root.val > val)
+            root = root.left;
+        else if (root.val < val)
+            root = root.right;
+        else 
+            return root;
+    }
+    return root;
+};
+```